High cholesterol could put women at risk of breast cancer, study suggests

Taking statins may cut the risk of breast cancer, scientists have said, after a new study uncovered the best evidence yet that having high cholesterol may put women at a higher risk.

The cholesterol-lowering drugs are already known to reduce the risk of heart attacks and strokes.

Although the new findings do not amount to direct evidence that high cholesterol causes breast cancer, they are a very strong indicator which experts said could lead to an “important future development” in our understanding of the disease.

The prospect of statins being used to reduce the risk of breast cancer, particularly among women with high cholesterol, is also causing excitement among cancer researchers. The drugs are cheap and are already taken by around seven million people in the UK at high risk of heart disease.

Being overweight or obese is already known to be a key risk factor for developing breast cancer. Overweight people are also more likely to have high cholesterol – a fatty substance in the blood, excess amounts of which can lead to dangerous fatty build-ups in the arteries that restrict blood flow and increase the risk of heart attacks and strokes.

Whether high cholesterol is the cause of obesity’s association with breast cancer is not known, nor is the exact mechanism by which high cholesterol might increase the risk of the disease.

However, the new findings, which are based on patient data from more than 660,000 women in the UK between 2000 and 2013, found that those with high cholesterol had a 1.64 times greater chance of developing breast cancer.

Dr Rahul Potluri, a cardiologist at Aston University in Birmingham, who led the study, said that while the “significant time and research” was needed before the idea of preventing breast cancer with statins could be tested, the findings were “exciting”.

“Statins are cheap, widely available and relatively safe,” he said. “We are potentially heading towards a clinical trial in 10 to 15 years to test the effect of statins on the incidence of breast cancer. If such a trial is successful, statins may have a role in the prevention of breast cancer, especially in high risk groups, such as women with high cholesterol.”

The study was presented at the Frontiers in Cardiovascular Biology conference in Barcelona today.

Dr Caroline Dalton, senior policy officer at the UK charity Breakthrough Breast Cancer, said: “Whilst it’s important to remember that this study doesn’t prove high cholesterol causes breast cancer it does present an engaging reason for why more research should be conducted in this particular area. It’s still too early to say whether lowering cholesterol, for example through the use of statins, can reduce the risk of breast cancer but this study is promising in that it may point us towards an important future development in our understanding of the disease.”